Rustdoc source links should link into expanded macros rather than to the macro invocation #146007
Description
This is a followup from discussing PR #137229 on reddit.
Specially that PR added the ability to (unstably) expand macros in rustdoc source view. A great next step would be to have links from the docs to the source to go into the expanded macro. For example: the methods on u32 currently point to the macro invocation but could point into the expanded macro. This would make it a lot easier to see the source for the integer types and other types where it macros are used to define the impl blocks.
@rustbot label -C-bug
(Please fix the labels, I couldn't find a suitable template for this, so I selected rustdoc bug.)